Definite Description (Logic) Has a Place in the Philosophy of Science

By Conrado D. Fontanilla

In the middle of theory making

To begin with, we must understand what “theory” means. Consider two definitions of theory, one by Norman Campbell, a British physicist, and another by Albert Einstein.

“How then does science explains laws? It explains them by means of ‘theories’ which are not laws, although closely related to laws” (Campbell, N. What Is Science? 1921:81).

Campbell proceeded in his definition by mentioning two laws and how theories explain them, to wit:

“Boyle’s Law states the pressure is inversely proportional to the volume, so that if the volume is halved the pressure is double; Gay-Lussac’s states that, at a constant volume, the pressure increases proportionally to the temperature (if a certain scale of temperature is adopted, slightly different from that in common use)….

“All these laws are ‘explained’ by a doctrine known as the Dynamical Theory of Gases, which was proposed early in the last century and is accepted universally to-day. According to this theory, a gas consists of an immense number of very small particles, called molecules, flying about in all directions, colliding with each other and with the wall of the containing vessel ; the speed of the flight of these molecules increases with the temperature ; their impacts on the walls of the vessel tends to force the walls outwards and represent the pressure on them ; and by their motion, heat is conveyed from one part of the gas to another in the manner called conduction (emphasis mine).

 I take it that the above italics in boldface is a theory in Campbell’s view. Campbell further qualifies what he means by theory:

“So far the truth of a theory has been based on two grounds : first, that the laws to be explained can be deduced from it ; second, that it really explains in the sense that has been indicated. But actually there is in addition, a third test of the truth of a theory, which is of great importance ; a true theory will not only explain adequately the laws that it was introduced to explain ; it will also predict and explain in advance laws which were unknown before” (Campbell, page 87).

I am looking into Campbell’s definition of a theory for what theory consists of. My framework  is:  whatever serve(s) as building block(s) of a theory; theory (theories) as building block(s) of a law of science;  laws of science; unification of laws.